Leading shares are edging lower in uncertain trading, with mining shares hit by poor Chinese data and disappointing updates from Pearson and easyJet.

The FTSE 100 is currently 3.17 points lower at 6823.16, having recovered from a dip to 6811 after European purchasing managers' surveys outweighed weakness in the Chinese equivalent.

Pearson is the biggest faller so far, down 103p at £11.95 after the publishing group warned 2013 earnings would be lower than expected due to higher restructuring costs and weak demand in its North American education business. Ian Whittaker at Liberum said education turned in a mixed performance, with emerging markets showing strong growth but development markets seeing weakness, but the real shock was on restructuring:

For 2014, the wording is slightly confusing, but it looks like Pearson is now guiding to net restructuring costs of £50m versus the suggested positive benefit (we had a £25m positive effect on operating profit for 2014).

While Pearson is still saying 2015 will be a growth year, the deeper restructuring charges - similar to what we have seen in other media sectors in the past that have been structurally challenged - suggest the structural pressures are accelerating.

EasyJet is down 42p at £17.01 after the low cost airline reported a 7.7% rise in first quarter revenues but cautioned that the time of Easter in April would fall outside its first half and affect the results for that period.

Mining shares have slipped after HSBC's purchasing managers' index for key commodities consumer China dipped to 49.6 this month from December's 50.5, the lowest since July.

So Glencore Xstrata is down 10p at 744.5p, Rio Tinto is 21p lower at £32.25 and BHP Billiton has slipped 12.5p to 1821.5p.

But Marks & Spencer has jumped 16.5p to 497.4p after Exane BNP Paribas moved from underperform to outperform. It said:

M&S has endured three years of difficult trading and profit declines. Margins have fallen to their lowest in a decade. Store refits and product revolutions have proven to be false dawns. In a fast-changing retail environment M&S has suffered from a history of underinvestment.

This is changing.

Within a year, an eCommerce solution will be launched and system improvements will go live. In 2015 the evolution of the supply chain will be complete. M&S is striking at the heart of recent difficulties.

These solutions drive a reversal in negative earnings momentum, and a 40% or so increase in pretax profit over the next three years. This looks inconsistent with valuation, which is near 10-year relative lows. Now is the time to look beyond recent troubles.